Peach Selenite (Satin Spar)
Gypsum var. Satin Spar · Semi-Precious Gemstone / Mineral Specimen
Crystal System
Monoclinic; typically occurs in fibrous, parallel aggregates known as Satin Spar
Mineral Group
Sulfates
Chemical Formula
CaSO4·2H2O (Hydrous calcium sulfate)
Formation Process
Sedimentary process through the evaporation of saline water (evaporite) or hydrothermal precipitation in caves and veins
About This Crystal
Translucent peach to orange-brown color with a distinct fibrous structure. It exhibits a silky, pearly luster and a characteristic 'cat's eye' shimmer when polished.
Physical Characteristics
Color: Peach/Orange; Streak: White; Cleavage: Perfect in one direction; Fracture: Splintery; Specific Gravity: 2.3; Fluorescence: Can show weak blue or white under UV
Optical Properties
Refractive Index: 1.520–1.530; Birefringence: 0.009; Displays strong chatoyancy (silky sheen) due to fibrous structure
Hardness & Durability
Origin Region
Morocco, Mexico, USA (Utah), and Brazil; typically found in evaporite basins
Hardness & Durability
Mohs Hardness: 2; very soft (can be scratched by a fingernail). Poor toughness; extremely brittle and water-soluble
Care & Maintenance
Avoid all water and humidity as it can dissolve or lose luster. Clean only with a dry soft cloth; store away from harder stones; sensitive to heat
Rarity & Value
Common; very affordable. Value is based on size, color saturation, and the quality of the chatoyancy
Special Characteristics
Strong chatoyant effect (optical silky sheen); fibrous 'satin' appearance; extremely low hardness
Lore & History
Historically named after the Greek moon goddess Selene. In metaphysical traditions, it is associated with the Sacral and Crown chakras, believed to promote emotional cleansing and mental clarity.